U.S. Patent Application Publication No. 2016/0082996 discloses a security cart having a rear wall, a wheeled base frame connected to the rear wall and a base shelf pivotable between a horizontal position and a raised position. A first sidewall and a first door pivotally connected to the first sidewall are movable from locked positions with the base shelf to a folded position forwardly of the rear wall. A second sidewall and a second door pivotally connected to the second sidewall are movable from locked positions to a folded position forwardly of the folded first sidewall and first door. The base shelf is movable from the horizontal position to the raised position, and retained against the folded first sidewall and the first door and the folded second sidewall and second door.
U.S. Pat. No. 9,428,205 discloses a security cart having a rear wall, a wheeled base frame connected to the rear wall and a base shelf pivotable between a horizontal position and a raised position. A first sidewall and a first door pivotally connected to the first sidewall are movable from locked positions with the base shelf to a folded position forwardly of the rear wall. A second sidewall and a second door pivotally connected to the second sidewall are movable from locked positions to a folded position forwardly of the folded first sidewall and first door. The base shelf is movable from the horizontal position to the raised position, and retained against the folded first sidewall and the first door and the folded second sidewall and second door.
U.S. Pat. No. 9,149,114 discloses a cabinet having a deep shelf with limited access is described and includes at least two opposite sides carrying track means to permit easy adjustment of the shelf between two or more levels by a single person maneuvering only the one accessible end of the shelf. The cabinet can be mounted on wheels to form a cart. One or more such adjustable shelves can be provided. The shelves may be positioned just above the bottom of the cart to provide a maximum depth cart for use, in intermediate positions for use with smaller objects and/or at the very top and/or side of the cart and locked in position to provide a secured interior for the cabinet.
U.S. Pat. No. 8,931,420 discloses a pallet or cart which can be coupled to a similar pallet or cart in a side by side relationship. The pallet or cart, at its one or right side, has a coupling, which cooperates with an associated coupling on the opposite or left side of an adjacent pallet or cart. The couplings and the associated couplings can be connected to connect the two pallets or carts together to make them capable of being moved together, and even be lifted and lowered together by a standard lift truck or fork lift or a standard pallet jack. The couplings are also releasable so that, when necessary, each pallet or cart may be used as would be a single pallet or cart. The pallet or cart may have one or more foldable shelves therein.